/* crypto/rand/rand_win.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */
/* ====================================================================
 * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@openssl.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include "cryptlib.h"
#include <openssl/rand.h>
#include "rand_lcl.h"

#if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
#include <windows.h>
#ifndef _WIN32_WINNT
# define _WIN32_WINNT 0x0400
#endif
#include <wincrypt.h>

#if OPENSSL_WINRT_DESKTOP || OPENSSL_WINRT_PHONE
#  include <sysinfoapi.h>	//For GetTickCount64
#  include "rand_winrt.h"
#else
#  include <tlhelp32.h>
#endif //WINAPI_PARTITION_PC_APP || WINAPI_PARTITION_PHONE_APP



/* Limit the time spent walking through the heap, processes, threads and modules to
   a maximum of 1000 miliseconds each, unless CryptoGenRandom failed */
#define MAXDELAY 1000

/* Intel hardware RNG CSP -- available from
 * http://developer.intel.com/design/security/rng/redist_license.htm
 */
#define PROV_INTEL_SEC 22
#define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"

static void readtimer(void);
static void readscreen(void);

/* It appears like CURSORINFO, PCURSORINFO and LPCURSORINFO are only defined
   when WINVER is 0x0500 and up, which currently only happens on Win2000.
   Unfortunately, those are typedefs, so they're a little bit difficult to
   detect properly.  On the other hand, the macro CURSOR_SHOWING is defined
   within the same conditional, so it can be use to detect the absence of said
   typedefs. */

#ifndef CURSOR_SHOWING
/*
 * Information about the global cursor.
 */
typedef struct tagCURSORINFO
{
	DWORD   cbSize;
	DWORD   flags;
	HCURSOR hCursor;
	POINT   ptScreenPos;
} CURSORINFO, *PCURSORINFO, *LPCURSORINFO;

#define CURSOR_SHOWING     0x00000001
#endif /* CURSOR_SHOWING */

#if !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
#if !defined(OPENSSL_SYS_WINCE)
typedef BOOL(WINAPI *CRYPTACQUIRECONTEXTW)(HCRYPTPROV *, LPCWSTR, LPCWSTR,
	DWORD, DWORD);
typedef BOOL(WINAPI *CRYPTGENRANDOM)(HCRYPTPROV, DWORD, BYTE *);
typedef BOOL(WINAPI *CRYPTRELEASECONTEXT)(HCRYPTPROV, DWORD);

typedef HWND(WINAPI *GETFOREGROUNDWINDOW)(VOID);
typedef BOOL(WINAPI *GETCURSORINFO)(PCURSORINFO);
typedef DWORD(WINAPI *GETQUEUESTATUS)(UINT);

typedef HANDLE(WINAPI *CREATETOOLHELP32SNAPSHOT)(DWORD, DWORD);
typedef BOOL(WINAPI *CLOSETOOLHELP32SNAPSHOT)(HANDLE);
typedef BOOL(WINAPI *HEAP32FIRST)(LPHEAPENTRY32, DWORD, size_t);
typedef BOOL(WINAPI *HEAP32NEXT)(LPHEAPENTRY32);
typedef BOOL(WINAPI *HEAP32LIST)(HANDLE, LPHEAPLIST32);
typedef BOOL(WINAPI *PROCESS32)(HANDLE, LPPROCESSENTRY32);
typedef BOOL(WINAPI *THREAD32)(HANDLE, LPTHREADENTRY32);
typedef BOOL(WINAPI *MODULE32)(HANDLE, LPMODULEENTRY32);

#include <lmcons.h>
#include <lmstats.h>
#if 1 /* The NET API is Unicode only.  It requires the use of the UNICODE
* macro.  When UNICODE is defined LPTSTR becomes LPWSTR.  LMSTR was
* was added to the Platform SDK to allow the NET API to be used in
* non-Unicode applications provided that Unicode strings were still
* used for input.  LMSTR is defined as LPWSTR.
*/
typedef NET_API_STATUS(NET_API_FUNCTION * NETSTATGET)
(LPWSTR, LPWSTR, DWORD, DWORD, LPBYTE*);
typedef NET_API_STATUS(NET_API_FUNCTION * NETFREE)(LPBYTE);
#endif /* 1 */
#endif /* !OPENSSL_SYS_WINCE */
#endif //!OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE

int RAND_poll(void)
{
#if !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
	MEMORYSTATUS m;
#endif
	HCRYPTPROV hProvider = 0;
	DWORD w;
	int good = 0;

#if !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
	/* Determine the OS version we are on so we can turn off things
	 * that do not work properly.
	 */
	OSVERSIONINFO osverinfo;
	osverinfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
	GetVersionEx(&osverinfo);
#endif

#if OPENSSL_WINRT_DESKTOP || OPENSSL_WINRT_PHONE
	BYTE buf[64];
	RAND_GenerateRandomBytes(buf, (int)sizeof(buf));
	RAND_add(buf, sizeof(buf), sizeof(buf));
#else
#if defined(OPENSSL_SYS_WINCE)
# if defined(_WIN32_WCE) && _WIN32_WCE>=300
	/* Even though MSDN says _WIN32_WCE>=210, it doesn't seem to be available
	 * in commonly available implementations prior 300... */
	{
		BYTE buf[64];
		/* poll the CryptoAPI PRNG */
		/* The CryptoAPI returns sizeof(buf) bytes of randomness */
		if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
			CRYPT_VERIFYCONTEXT))
		{
			if (CryptGenRandom(hProvider, sizeof(buf), buf))
				RAND_add(buf, sizeof(buf), sizeof(buf));
			CryptReleaseContext(hProvider, 0);
		}
	}
# endif
#else	/* OPENSSL_SYS_WINCE */
	/*
	 * None of below libraries are present on Windows CE, which is
	 * why we #ifndef the whole section. This also excuses us from
	 * handling the GetProcAddress issue. The trouble is that in
	 * real Win32 API GetProcAddress is available in ANSI flavor
	 * only. In WinCE on the other hand GetProcAddress is a macro
	 * most commonly defined as GetProcAddressW, which accepts
	 * Unicode argument. If we were to call GetProcAddress under
	 * WinCE, I'd recommend to either redefine GetProcAddress as
	 * GetProcAddressA (there seem to be one in common CE spec) or
	 * implement own shim routine, which would accept ANSI argument
	 * and expand it to Unicode.
	 */
	{
		/* load functions dynamically - not available on all systems */
		HMODULE advapi = LoadLibrary(TEXT("ADVAPI32.DLL"));
		HMODULE kernel = LoadLibrary(TEXT("KERNEL32.DLL"));
		HMODULE user = NULL;
		HMODULE netapi = LoadLibrary(TEXT("NETAPI32.DLL"));
		CRYPTACQUIRECONTEXTW acquire = NULL;
		CRYPTGENRANDOM gen = NULL;
		CRYPTRELEASECONTEXT release = NULL;
		NETSTATGET netstatget = NULL;
		NETFREE netfree = NULL;
		BYTE buf[64];

		if (netapi)
		{
			netstatget = (NETSTATGET)GetProcAddress(netapi, "NetStatisticsGet");
			netfree = (NETFREE)GetProcAddress(netapi, "NetApiBufferFree");
		}

		if (netstatget && netfree)
		{
			LPBYTE outbuf;
			/* NetStatisticsGet() is a Unicode only function
			 * STAT_WORKSTATION_0 contains 45 fields and STAT_SERVER_0
			 * contains 17 fields.  We treat each field as a source of
			 * one byte of entropy.
			 */

			if (netstatget(NULL, L"LanmanWorkstation", 0, 0, &outbuf) == 0)
			{
				RAND_add(outbuf, sizeof(STAT_WORKSTATION_0), 45);
				netfree(outbuf);
			}
			if (netstatget(NULL, L"LanmanServer", 0, 0, &outbuf) == 0)
			{
				RAND_add(outbuf, sizeof(STAT_SERVER_0), 17);
				netfree(outbuf);
			}
		}

		if (netapi)
			FreeLibrary(netapi);

		/* It appears like this can cause an exception deep within ADVAPI32.DLL
		 * at random times on Windows 2000.  Reported by Jeffrey Altman.
		 * Only use it on NT.
		 */
		/* Wolfgang Marczy <WMarczy@topcall.co.at> reports that
		 * the RegQueryValueEx call below can hang on NT4.0 (SP6).
		 * So we don't use this at all for now. */
#if 0
		if (osverinfo.dwPlatformId == VER_PLATFORM_WIN32_NT &&
			osverinfo.dwMajorVersion < 5)
		{
			/* Read Performance Statistics from NT/2000 registry
			 * The size of the performance data can vary from call
			 * to call so we must guess the size of the buffer to use
			 * and increase its size if we get an ERROR_MORE_DATA
			 * return instead of ERROR_SUCCESS.
			 */
			LONG   rc = ERROR_MORE_DATA;
			char * buf = NULL;
			DWORD bufsz = 0;
			DWORD length;

			while (rc == ERROR_MORE_DATA)
			{
				buf = realloc(buf, bufsz + 8192);
				if (!buf)
					break;
				bufsz += 8192;

				length = bufsz;
				rc = RegQueryValueEx(HKEY_PERFORMANCE_DATA, TEXT("Global"),
					NULL, NULL, buf, &length);
			}
			if (rc == ERROR_SUCCESS)
			{
				/* For entropy count assume only least significant
	 * byte of each DWORD is random.
	 */
				RAND_add(&length, sizeof(length), 0);
				RAND_add(buf, length, length / 4.0);

				/* Close the Registry Key to allow Windows to cleanup/close
				 * the open handle
				 * Note: The 'HKEY_PERFORMANCE_DATA' key is implicitly opened
				 *       when the RegQueryValueEx above is done.  However, if
				 *       it is not explicitly closed, it can cause disk
				 *       partition manipulation problems.
				 */
				RegCloseKey(HKEY_PERFORMANCE_DATA);
			}
			if (buf)
				free(buf);
		}
#endif

		if (advapi)
		{
			/*
			 * If it's available, then it's available in both ANSI
			 * and UNICODE flavors even in Win9x, documentation says.
			 * We favor Unicode...
			 */
			acquire = (CRYPTACQUIRECONTEXTW)GetProcAddress(advapi,
				"CryptAcquireContextW");
			gen = (CRYPTGENRANDOM)GetProcAddress(advapi,
				"CryptGenRandom");
			release = (CRYPTRELEASECONTEXT)GetProcAddress(advapi,
				"CryptReleaseContext");
		}

		if (acquire && gen && release)
		{
			/* poll the CryptoAPI PRNG */
			/* The CryptoAPI returns sizeof(buf) bytes of randomness */
			if (acquire(&hProvider, NULL, NULL, PROV_RSA_FULL,
				CRYPT_VERIFYCONTEXT))
			{
				if (gen(hProvider, sizeof(buf), buf) != 0)
				{
					RAND_add(buf, sizeof(buf), 0);
					good = 1;
#if 0
					printf("randomness from PROV_RSA_FULL\n");
#endif
				}
				release(hProvider, 0);
			}

			/* poll the Pentium PRG with CryptoAPI */
			if (acquire(&hProvider, 0, INTEL_DEF_PROV, PROV_INTEL_SEC, 0))
			{
				if (gen(hProvider, sizeof(buf), buf) != 0)
				{
					RAND_add(buf, sizeof(buf), sizeof(buf));
					good = 1;
#if 0
					printf("randomness from PROV_INTEL_SEC\n");
#endif
				}
				release(hProvider, 0);
			}
		}

		if (advapi)
			FreeLibrary(advapi);

#if !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
		if ((osverinfo.dwPlatformId != VER_PLATFORM_WIN32_NT ||
			!OPENSSL_isservice()) &&
			(user = LoadLibrary(TEXT("USER32.DLL"))))
		{
			GETCURSORINFO cursor;
			GETFOREGROUNDWINDOW win;
			GETQUEUESTATUS queue;

			win = (GETFOREGROUNDWINDOW)GetProcAddress(user, "GetForegroundWindow");
			cursor = (GETCURSORINFO)GetProcAddress(user, "GetCursorInfo");
			queue = (GETQUEUESTATUS)GetProcAddress(user, "GetQueueStatus");

			if (win)
			{
				/* window handle */
				HWND h = win();
				RAND_add(&h, sizeof(h), 0);
			}
			if (cursor)
			{
				/* unfortunately, its not safe to call GetCursorInfo()
				 * on NT4 even though it exists in SP3 (or SP6) and
				 * higher.
				 */
				if (osverinfo.dwPlatformId == VER_PLATFORM_WIN32_NT &&
					osverinfo.dwMajorVersion < 5)
					cursor = 0;
			}
			if (cursor)
			{
				/* cursor position */
				/* assume 2 bytes of entropy */
				CURSORINFO ci;
				ci.cbSize = sizeof(CURSORINFO);
				if (cursor(&ci))
					RAND_add(&ci, ci.cbSize, 2);
			}

			if (queue)
			{
				/* message queue status */
				/* assume 1 byte of entropy */
				w = queue(QS_ALLEVENTS);
				RAND_add(&w, sizeof(w), 1);
			}

			FreeLibrary(user);
		}
#endif
		/* Toolhelp32 snapshot: enumerate processes, threads, modules and heap
		 * http://msdn.microsoft.com/library/psdk/winbase/toolhelp_5pfd.htm
		 * (Win 9x and 2000 only, not available on NT)
		 *
		 * This seeding method was proposed in Peter Gutmann, Software
		 * Generation of Practically Strong Random Numbers,
		 * http://www.usenix.org/publications/library/proceedings/sec98/gutmann.html
		 * revised version at http://www.cryptoengines.com/~peter/06_random.pdf
		 * (The assignment of entropy estimates below is arbitrary, but based
		 * on Peter's analysis the full poll appears to be safe. Additional
		 * interactive seeding is encouraged.)
		 */

		if (kernel)
		{
			CREATETOOLHELP32SNAPSHOT snap;
			CLOSETOOLHELP32SNAPSHOT close_snap;
			HANDLE handle;

			HEAP32FIRST heap_first;
			HEAP32NEXT heap_next;
			HEAP32LIST heaplist_first, heaplist_next;
			PROCESS32 process_first, process_next;
			THREAD32 thread_first, thread_next;
			MODULE32 module_first, module_next;

			HEAPLIST32 hlist;
			HEAPENTRY32 hentry;
			PROCESSENTRY32 p;
			THREADENTRY32 t;
			MODULEENTRY32 m;
			DWORD starttime = 0;

			snap = (CREATETOOLHELP32SNAPSHOT)
				GetProcAddress(kernel, "CreateToolhelp32Snapshot");
			close_snap = (CLOSETOOLHELP32SNAPSHOT)
				GetProcAddress(kernel, "CloseToolhelp32Snapshot");
			heap_first = (HEAP32FIRST)GetProcAddress(kernel, "Heap32First");
			heap_next = (HEAP32NEXT)GetProcAddress(kernel, "Heap32Next");
			heaplist_first = (HEAP32LIST)GetProcAddress(kernel, "Heap32ListFirst");
			heaplist_next = (HEAP32LIST)GetProcAddress(kernel, "Heap32ListNext");
			process_first = (PROCESS32)GetProcAddress(kernel, "Process32First");
			process_next = (PROCESS32)GetProcAddress(kernel, "Process32Next");
			thread_first = (THREAD32)GetProcAddress(kernel, "Thread32First");
			thread_next = (THREAD32)GetProcAddress(kernel, "Thread32Next");
			module_first = (MODULE32)GetProcAddress(kernel, "Module32First");
			module_next = (MODULE32)GetProcAddress(kernel, "Module32Next");

			if (snap && heap_first && heap_next && heaplist_first &&
				heaplist_next && process_first && process_next &&
				thread_first && thread_next && module_first &&
				module_next && (handle = snap(TH32CS_SNAPALL, 0))
				!= INVALID_HANDLE_VALUE)
			{
				/* heap list and heap walking */
				/* HEAPLIST32 contains 3 fields that will change with
				 * each entry.  Consider each field a source of 1 byte
				 * of entropy.
				 * HEAPENTRY32 contains 5 fields that will change with
				 * each entry.  Consider each field a source of 1 byte
				 * of entropy.
				 */
				ZeroMemory(&hlist, sizeof(HEAPLIST32));
				hlist.dwSize = sizeof(HEAPLIST32);
				if (good) starttime = GetTickCount();
#ifdef _MSC_VER
				if (heaplist_first(handle, &hlist))
				{
					/*
					   following discussion on dev ML, exception on WinCE (or other Win
					   platform) is theoretically of unknown origin; prevent infinite
					   loop here when this theoretical case occurs; otherwise cope with
					   the expected (MSDN documented) exception-throwing behaviour of
					   Heap32Next() on WinCE.

					   based on patch in original message by Tanguy Fautré (2009/03/02)
					   Subject: RAND_poll() and CreateToolhelp32Snapshot() stability
					   */
					int ex_cnt_limit = 42;
					do
					{
						RAND_add(&hlist, hlist.dwSize, 3);
						__try
						{
							ZeroMemory(&hentry, sizeof(HEAPENTRY32));
							hentry.dwSize = sizeof(HEAPENTRY32);
							if (heap_first(&hentry,
								hlist.th32ProcessID,
								hlist.th32HeapID))
							{
								int entrycnt = 80;
								do
								RAND_add(&hentry,
									hentry.dwSize, 5);
								while (heap_next(&hentry)
									&& (!good || (GetTickCount() - starttime)<MAXDELAY)
									&& --entrycnt > 0);
							}
						}
						__except (EXCEPTION_EXECUTE_HANDLER)
						{
							/* ignore access violations when walking the heap list */
							ex_cnt_limit--;
						}
					} while (heaplist_next(handle, &hlist)
						&& (!good || (GetTickCount() - starttime)<MAXDELAY)
						&& ex_cnt_limit > 0);
				}

#else
				if (heaplist_first(handle, &hlist))
				{
					do
					{
						RAND_add(&hlist, hlist.dwSize, 3);
						hentry.dwSize = sizeof(HEAPENTRY32);
						if (heap_first(&hentry,
							hlist.th32ProcessID,
							hlist.th32HeapID))
						{
							int entrycnt = 80;
							do
							RAND_add(&hentry,
								hentry.dwSize, 5);
							while (heap_next(&hentry)
								&& --entrycnt > 0);
						}
					} while (heaplist_next(handle, &hlist)
						&& (!good || (GetTickCount() - starttime) < MAXDELAY));
				}
#endif

				/* process walking */
				/* PROCESSENTRY32 contains 9 fields that will change
				 * with each entry.  Consider each field a source of
				 * 1 byte of entropy.
				 */
				p.dwSize = sizeof(PROCESSENTRY32);

				if (good) starttime = GetTickCount();
				if (process_first(handle, &p))
				do
				RAND_add(&p, p.dwSize, 9);
				while (process_next(handle, &p) && (!good || (GetTickCount() - starttime) < MAXDELAY));

				/* thread walking */
				/* THREADENTRY32 contains 6 fields that will change
				 * with each entry.  Consider each field a source of
				 * 1 byte of entropy.
				 */
				t.dwSize = sizeof(THREADENTRY32);
				if (good) starttime = GetTickCount();
				if (thread_first(handle, &t))
				do
				RAND_add(&t, t.dwSize, 6);
				while (thread_next(handle, &t) && (!good || (GetTickCount() - starttime) < MAXDELAY));

				/* module walking */
				/* MODULEENTRY32 contains 9 fields that will change
				 * with each entry.  Consider each field a source of
				 * 1 byte of entropy.
				 */
				m.dwSize = sizeof(MODULEENTRY32);
				if (good) starttime = GetTickCount();
				if (module_first(handle, &m))
				do
				RAND_add(&m, m.dwSize, 9);
				while (module_next(handle, &m)
					&& (!good || (GetTickCount() - starttime) < MAXDELAY));
				if (close_snap)
					close_snap(handle);
				else
					CloseHandle(handle);

			}

			FreeLibrary(kernel);
		}
	}
#endif /* !OPENSSL_SYS_WINCE */
#endif //OPENSSL_WINRT_DESKTOP || OPENSSL_WINRT_PHONE

	/* timer data */
	readtimer();

#if !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
	/* memory usage statistics */
	GlobalMemoryStatus(&m);
	RAND_add(&m, sizeof(m), 1);
#endif

	/* process ID */
	w = GetCurrentProcessId();
	RAND_add(&w, sizeof(w), 1);

#if 0
	printf("Exiting RAND_poll\n");
#endif

	return(1);
}

int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam)
{
	double add_entropy = 0;

	switch (iMsg)
	{
	case WM_KEYDOWN:
	{
					   static WPARAM key;
					   if (key != wParam)
						   add_entropy = 0.05;
					   key = wParam;
	}
		break;
	case WM_MOUSEMOVE:
	{
						 static int lastx, lasty, lastdx, lastdy;
						 int x, y, dx, dy;

						 x = LOWORD(lParam);
						 y = HIWORD(lParam);
						 dx = lastx - x;
						 dy = lasty - y;
						 if (dx != 0 && dy != 0 && dx - lastdx != 0 && dy - lastdy != 0)
							 add_entropy = .2;
						 lastx = x, lasty = y;
						 lastdx = dx, lastdy = dy;
	}
		break;
	}

	readtimer();
	RAND_add(&iMsg, sizeof(iMsg), add_entropy);
	RAND_add(&wParam, sizeof(wParam), 0);
	RAND_add(&lParam, sizeof(lParam), 0);

	return (RAND_status());
}


void RAND_screen(void) /* function available for backward compatibility */
{
	RAND_poll();
	readscreen();
}


/* feed timing information to the PRNG */
static void readtimer(void)
{
#if OPENSSL_WINRT_DESKTOP || OPENSSL_WINRT_PHONE
	ULONGLONG w;
#else
	DWORD w;
#endif
	LARGE_INTEGER l;
	static int have_perfc = 1;
#if defined(_MSC_VER) && defined(_M_X86)
	static int have_tsc = 1;
	DWORD cyclecount;

	if (have_tsc) {
		__try {
			__asm {
				_emit 0x0f
					_emit 0x31
					mov cyclecount, eax
			}
			RAND_add(&cyclecount, sizeof(cyclecount), 1);
		}
		__except (EXCEPTION_EXECUTE_HANDLER) {
			have_tsc = 0;
		}
	}
#else
# define have_tsc 0
#endif

	if (have_perfc) {
		if (QueryPerformanceCounter(&l) == 0)
			have_perfc = 0;
		else
			RAND_add(&l, sizeof(l), 0);
	}

	if (!have_tsc && !have_perfc) {
#if OPENSSL_WINRT_DESKTOP || OPENSSL_WINRT_PHONE
		w = GetTickCount64();
#else
		w = GetTickCount();
#endif
		RAND_add(&w, sizeof(w), 0);
	}
}

/* feed screen contents to PRNG */
/*****************************************************************************
 *
 * Created 960901 by Gertjan van Oosten, gertjan@West.NL, West Consulting B.V.
 *
 * Code adapted from
 * <URL:http://support.microsoft.com/default.aspx?scid=kb;[LN];97193>;
 * the original copyright message is:
 *
 *   (C) Copyright Microsoft Corp. 1993.  All rights reserved.
 *
 *   You have a royalty-free right to use, modify, reproduce and
 *   distribute the Sample Files (and/or any modified version) in
 *   any way you find useful, provided that you agree that
 *   Microsoft has no warranty obligations or liability for any
 *   Sample Application Files which are modified.
 */

static void readscreen(void)
{
#if !defined(OPENSSL_SYS_WINCE) && !defined(OPENSSL_SYS_WIN32_CYGWIN) && !OPENSSL_WINRT_DESKTOP && !OPENSSL_WINRT_PHONE
	HDC		hScrDC;		/* screen DC */
	HDC		hMemDC;		/* memory DC */
	HBITMAP	hBitmap;	/* handle for our bitmap */
	HBITMAP	hOldBitmap;	/* handle for previous bitmap */
	BITMAP	bm;		/* bitmap properties */
	unsigned int	size;		/* size of bitmap */
	char		*bmbits;	/* contents of bitmap */
	int		w;		/* screen width */
	int		h;		/* screen height */
	int		y;		/* y-coordinate of screen lines to grab */
	int		n = 16;		/* number of screen lines to grab at a time */

	if (GetVersion() < 0x80000000 && OPENSSL_isservice()>0)
		return;

	/* Create a screen DC and a memory DC compatible to screen DC */
	hScrDC = CreateDC(TEXT("DISPLAY"), NULL, NULL, NULL);
	hMemDC = CreateCompatibleDC(hScrDC);

	/* Get screen resolution */
	w = GetDeviceCaps(hScrDC, HORZRES);
	h = GetDeviceCaps(hScrDC, VERTRES);

	/* Create a bitmap compatible with the screen DC */
	hBitmap = CreateCompatibleBitmap(hScrDC, w, n);

	/* Select new bitmap into memory DC */
	hOldBitmap = SelectObject(hMemDC, hBitmap);

	/* Get bitmap properties */
	GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&bm);
	size = (unsigned int)bm.bmWidthBytes * bm.bmHeight * bm.bmPlanes;

	bmbits = OPENSSL_malloc(size);
	if (bmbits) {
		/* Now go through the whole screen, repeatedly grabbing n lines */
		for (y = 0; y < h - n; y += n)
		{
			unsigned char md[MD_DIGEST_LENGTH];

			/* Bitblt screen DC to memory DC */
			BitBlt(hMemDC, 0, 0, w, n, hScrDC, 0, y, SRCCOPY);

			/* Copy bitmap bits from memory DC to bmbits */
			GetBitmapBits(hBitmap, size, bmbits);

			/* Get the hash of the bitmap */
			MD(bmbits, size, md);

			/* Seed the random generator with the hash value */
			RAND_add(md, MD_DIGEST_LENGTH, 0);
		}

		OPENSSL_free(bmbits);
	}

	/* Select old bitmap back into memory DC */
	hBitmap = SelectObject(hMemDC, hOldBitmap);

	/* Clean up */
	DeleteObject(hBitmap);
	DeleteDC(hMemDC);
	DeleteDC(hScrDC);
#endif /* !OPENSSL_SYS_WINCE */
}

#endif
